Plow



April 27 1965 w. R. BERTELsEN 3,180,432

PLOW

Filed sept. 4, 1962 ENGINE COMPRESSOR United States Patent O PLOW William R. Bertelsen, Neponset, Ill. Filed Sept. 4, 1962, Ser. No. 221,669 12 Claims. (Cl. 172-755) The present invention relates generally to plows, and more particularly to a new plow provided with compressed air for supporting a plowed strip of earth at the time of turning the strip, and relates to improvements in my copending application Serial No. 815,114, now Patent No. 3,063,505.

At the present time conventional plows are made of different materials depending upon the uses to which they are to be put in different types of soils. Plain cast iron is used in some parts of the world for plowing sandy soils which can scour (abrasively polish) such plows easily. However, cast iron hardened by special processes at greater cost is preferred because of substantially better scouring properties. Crucible steel, although still more costly, is generally used because of still better scouring properties and its high resistance to breakage. For each material used, however, it is noteworthy that the scouring or polishing property is an attribute considered in its selection. On the other hand, such scouring is a kind of wearing away of the earth engaging surfaces of the plow. This wearing away reduces the useful life of the plow and necessitates frequent repair or replacement of plows and parts thereof.

It is a broad object of my present invention to provide a plow with a scouring function to maintain abrasive polishing at a low value regarding Wearing away of surfaces of the plow.

The term scouring function as used in the following disclosure defines a minimum of soil-caused abrasion to the surface of the plow during passage of the plow through the soil; the term does not dene rubbing with rough material to polish or shine.

A series of experiments with a plow having a moldboard face constructed substantially as illustrated in the accompanying drawing has brought forth certain discoveries comprising improvements upon the structure shown in the above mentioned patent and adaptable to more conventional shapes of plows. It has been found that a relatively high air pressure adjacent the point of the share of the plow and a relatively low air pressure adjacentthe moldboard thereof will effect the most uniform scouring of the plow. Such experiments indicate that a uniformly falling pressure from a high pressure at the leading point of the share Yto a low pressure at the trailing edge of the moldboard may obtain Ithe optimum scouring function for a given soil condition or constituency.

The present invention operates, as far as presently understood, in the following manner. High pressure air is introduced between the point of the share and the soil as the point is pulled into same. This air tends to expand and lift the soil. Rearwardly adjacent surfaces of the plow are supplied with air at lower pressures to hold the earth away from the surfaces a small-distance sucient to prevent a high rate of bleeding of air out into the atmosphere, but far enough away to float the soil along the plow surfaces while turning the soil. If pieces of soil should adhere to the plow, they apparently are rolled away by following soil. Thus the soil performs a scouring function without apparent or excessive abrasion of plow surfaces.

For further detail, reference will be made to the accompanying drawing, in which:

FG. l is a diagrammatic perspective View of a preferred embodiment of a plow;

FIG. 2 is an enlarged sectional view taken on line 2 2 of FIG. l;

lhAZ Patented Apr. 2'?, 1965 FG. 3 is a view similar to FIG. 1, showing a modification of the invention with parts broken away to show otherwise hidden details; and,

FIG. 4 is an enlarged sectional view taken on line ll-4 of FIG. 3.

Although the moldboard of the plow now to be described in detail can be cast of different metals including those considered soft such as iron, aluminum, magnesium, pot metal, and the like, this disclosure concerns a plow made of relatively inexpensive sheet steel parts welded together to make a strong but light weight plow.

The present plow comprises a narrow share 10 having a point lll, a perforated moldboard l2, a back plate 14 shaped and sized substantially the same as the moldboard, and partition plates la. The moldboard l2 is preferably made of sheet steel having uniformly spaced perforations 18 therein. As one example, and not in a limiting sense, Such perforations may be one-sixteenth inch diameter holes punched on one inch centers thus providing approximately one 4hundred and forty four holes per square foot of surface and slightly less than one half of a square inch of opening through the surface per square foot of surface. f Y

The share lll is preferably made of crucible steel, or the like, having high abrasion resistance. Such a share is also desired for use with cast plow moldboards to resist abrasion. The share l@ can be bolted to cast plows, but is shown as welded to the sheet metal moldboard parts. The partition plates 16 are also welded to the moldboard 12 and the back plate ld. The moldboard l2, the back plate id, and the share lt) are welded together all around the edges of the moldboard 12 and back plate 14 to form an airtight seal. The plates i6 are further projection welded to the moldboard l2 and back plate le to form substantially airtight partitions within the plow, and to strengthen the structure in the manner of a box beam. This makes a light weight but strong plow.

It is to be noted in FIG. 1 that the plates 16 form three interior air compartments within the plow. There could be more compartments within the scope of the invention; but at least two are deemed necessary. The leading chamber adjacent the point 1l is relatively small in volume and in area of moldboard lll due to lthe required shape of a plow. In order to use inexpensive perforated sheet steel for the entire moldboard, it is advisable to provide either more or larger holes *alla adjacent the point 1l. In rearwardly successive chambers it is also desirable to provide either more or larger holes 18ct in the moldboard l2 closely adjacent the share lll to enhance the scouring function.

Air at different pressures is fed to the compartments from a source of compressed air 2@ which may be a compressor driven by a tractor engine, not shown, for example. A header pipe 22 supplies air through a control valve 24 at fifty to one hundred pounds pressure, for example, to a exible pipe 2S to a connection 26 in air communication with the chamber adjacent the leading tip 11 of the share ll). Medium pressure air at twentylive to fifty pounds pressure, for example, is fed to the intermediate chamber from header 22 through a control valve 2d, flexible pipe 29, and a connection El). Low pressure air at live to ten pounds per square inch, for example, is supplied to the rear moldboard chamber from header 22 through a control valve 32, flexible pipe 33 and connection 34. The flexible pipes 25, 29 and 33 can be included in a single casing conveniently, if desired.

The pressures stated above are by way of example only and can be varied substantially. For example, the density of the soil, depth of furrow, and frontal width of the plow, and other factors can influence the selection of the bst range of pressures. The quantity of air will also vary with plow size. The specific perforations and open areas q 9 for a plow given above are for a twelve to sixteen inch width plow considered conventional for normal agricultural purposes.V Y

FIGS. 3 and 4 show a modification of the invention for f Supplying air under pressure only to the leading chamber adjacent the point 11 of the plow. The plow is built identically to the above described plow except for additional partition plates 116 (live being shown) having Oriccs therein and a single large' pressurized air supply conhection 126. This modilication has the advantage of only'one air connection which is adjacent the point of the plow. High pressure air is supplied to the point of the lin connection with orices 117, if desired.v For substantially larger plows than shown several more Oriiiced plates 116 may be desirable both for strength and greater pressure control.

I plow through perforations 18; successively lower pressure VVv'hile I have shown and described in detail two modiconnected between said front and back plates andto sub-V stantially Opposite points of said periphery Vto form a plucations of ythis invention, obviously other modiicationsv front plate Vand being connected to said front plate at 4the periphery thereof, and internalplates connected between said front and back plates and to substantially opposite .top and bottom points of said periphery to form a plurality of rearwardlyv successively spaced from said point chambers within said moldboard; an'engine driven compressor for providing a continuous sourceof'pressurized air; and means connected between said source and chambers for supplying air at dierent pressures with relationship to diierent chambers, said means supplying relative: ly higherpressure air to the chamber adjacent said point o said share than to other chambers. y v Y 5. The plow recited in claim l, said perforations being substantially uniformly sized.

Oriiices of predetermined Varea in said internal plates to supply pressurized air successively from one chamber to the next. K

V7. A plow adapted for plowing earth comprising in combination; a share for cutting a strip of earth; a moldboard for Vturning said strip. of earth comprising a frontv yplate having a predetermined pattern of relatively small perforations, and a back plate connected to said front plate adjacent the'edges thereof, being spaced therefrom and circumscribing the perforations therein; said moldboard being connected with said shareg'meansincluding an engine driven compressor and piping to said plow for Suprality of Vchambers within said moldboard;an engine driven compressor for providing a continuous source of pressurized air; and means connected between said source and said chambers for supplying air at dilerent pressures with relationship to diierent chambers. f

2. A plow comprising in combination; ashare for cutting a strip of earth; a moldboard connected to said share for turning said strip of earth; said moldboard including a pertorated front plate, a back plate connected to said front plate at the periphery thereof and being spaced therefrom 'a predetermined distance, and internal plates connected between said front and back plates and Vto substantially opposite points of said periphery to form a plurality of chambers within saidzmoldboarchan engine driven compressor for providing a continuous source of pressurized air; and means connected between. said source and said V chambers for supplying air at different pressures with relationship to different chambers, said means supplying the greatest mass of air adjacent said share. I

3. A plow comprising'in combination; a sharehaving a point for cutting a strip of earth; ya moldboard connected to saidy share for turning said strip of earth; said mold-l Vboard including a substantiallyuniformly perforated front plate, a back plate spaced from and sealingly connected to said front'plate at the periphery thereof, and internal plates sealingly connected between said front and back plates and Vto substantially opposite top and'bottom points yor? saidv periphery tO form a plurality Of chambers within said moldboard; an engine riven compressor for providing a continuous source of pressurized air; and means, connected between said source and said chambers for supplying air at vdifferent pressures with relationship tO different chambers, said means supplying the highest pressure air to the chamber nearest to said point.

4. A plow comprising in combination; a share having a point and a shearing edge for cutting a strip of earth; a

' moldboardrconnected to said share for turning said strip Y of earth; said moldboard including Va front plate having substantiallyv uniformly spacedV perforations therein, a back plate of substantially the same size (and shape as said plying a I irst predetermined mass of pressurized air to a n part of the space between said front and back plates adjacent said share; and second means for supplying a second predetermined mass of pressurized air to another part of the space between said plates. y

v8. Av plowfadapted for plowing earth comprising in combination; a share -for cutting a strip of earth; a moldboard for turning said strip of earth comprising a front f plate having a predetermined patternof-relatively small perforations,V anda backplate connected to said front plate adjacent the edges thereof, being spaced therefrom and circumscribing the perforations therein; said moldboard being connected with said share; meansV including an engine drivencompressor and piping to said plow for supplying relativelyhigh pressure airfto a part of the space between said front and back plates adjacent said share; and second means for supplying relatively low/ pressure air to another part of the spacerbetwcen said plates.

9., The plow of claim 7, said second means comprising meansV for controlling the relative pressure of air `of at Y, least two parts'of thevspace'between said plates.

l0. The plow of claim 7,V said second means comprising atleast one partition having an Vorifice and being connected between said front andba'ck plate.

11. The .plow of claim 9, said control means comprising'spaced apart plates having air ow'control orifices, said plates defining chambers in the space between said front and back plates.

l2.A The plow of claim 7, said front and rear plates being further connected together to form at least twochambers, One'charnber being adjacent said share; and said air f supply means including air low control means interposed between said two chambers. i

References .Cited by the Examiner UNITED STATES PATENTS 223,124 12/79 Fields 172-755 310,249 -r/s5 Brown 172-755 1,445,148y .2/23y Ledbetr ---1., 172-755 V2,222,437V 11/40 `Lykken 37-19 X Y 2,436,956 s/Ltsr Du rias 37-19 X l .Y 'l FOREIGN PArENrsy l 116,485 V3/58 Russia. y

Y SAMUEL KOKEN, Primary Examiner.

A. Y:rOsEPn GOLDBERG, LUCIE H. LAUDENSLAG- ER, Examiners.A Y

Y 6. Thev plow recited in claim 1, said means including i 

1. A PLOW COMPRISING IN COMBINATION; A SHARE FOR CUTTING A STRIP OF EARTH; A MOLDBOARD CONNECTED TO SAID SHARE FOR TURNING SAID STRIP OF EARTH; SAID MOLDBOARD INCLUDING A PERFORATED FRONT PLATE, A BACK LATE CONNECTED TO SAID FRONT PLATE AT THE PERIPHERY THEREOF, AND INTERNAL PLATES CONNECTED BETWEEN SAID FRONT AND BACK PLATES AND TO SUBSTANTIALLY OPPOSITE POINTS OF SAID PERIPHERY TO FOMR A PLURALITY OF CHAMBERS WITHIN SAID MOLDBOARD; AN ENGINE DRIVEN COMPRESSOR FOR PROVIDING A CONTINUOUS SOURCE OF PRESSURIZED AIR; AND MEANS CONNECTED BETWEEN SAID SOURCE AND SAID CHAMBERS FOR SUPPLYING AIR AT DIFFERENT PRESSURES WITH RELATIONSHIP TO DIFFERENT CHAMBERS. 